Oxypleurodon Miers, 1886

Remarks. The genus Oxypleurodon Miers, 1886, was recently reviewed and redefined by Richer de Forges and Ng (in press). In this paper, two new genera and several new species were described, and the differences as well as relationship with Sphenocarcinus A. Milne-Edwards, 1875, were treated at length. There have been many discussions during the last 20 years about the relationship between Oxypleurodon Miers, 1886, and Rochinia Milne-Edwards, 1875 (see Guinot & Richer de Forges 1986; Griffin & Tranter 1986; Tavares 1991; Richer de Forges 1995, Webber & Richer de Forges 1995; Ng & Richer de Forges 2007; Richer de Forges & Ng in press), but the current consensus is that they are separate genera (see Ng et al. 2008; Richer de Forges & Ng in press). Garth (1958: 282), with his usual insight, had already identified one key character in separating Rochinia from Oxypleurodon: the hepatic and branchial spines are always prominent and very conspicuous in Rochinia, while in Oxypleurodon, the hepatic and branchial regions bear plates.